1 files changed, 24 insertions, 34 deletions

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 2fe396385a4a..108a352051be 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -525,7 +525,7 @@ void blk_mq_free_request(struct request *rq)
 		__blk_mq_dec_active_requests(hctx);
 
 	if (unlikely(laptop_mode && !blk_rq_is_passthrough(rq)))
-		laptop_io_completion(q->backing_dev_info);
+		laptop_io_completion(q->disk->bdi);
 
 	rq_qos_done(q, rq);
 
@@ -606,7 +606,7 @@ static inline bool blk_mq_complete_need_ipi(struct request *rq)
 	 * This is probably worse than completing the request on a different
 	 * cache domain.
 	 */
-	if (force_irqthreads)
+	if (force_irqthreads())
 		return false;
 
 	/* same CPU or cache domain?  Complete locally */
@@ -911,7 +911,7 @@ static bool blk_mq_req_expired(struct request *rq, unsigned long *next)
 
 void blk_mq_put_rq_ref(struct request *rq)
 {
-	if (is_flush_rq(rq, rq->mq_hctx))
+	if (is_flush_rq(rq))
 		rq->end_io(rq, 0);
 	else if (refcount_dec_and_test(&rq->ref))
 		__blk_mq_free_request(rq);
@@ -923,34 +923,14 @@ static bool blk_mq_check_expired(struct blk_mq_hw_ctx *hctx,
 	unsigned long *next = priv;
 
 	/*
-	 * Just do a quick check if it is expired before locking the request in
-	 * so we're not unnecessarilly synchronizing across CPUs.
-	 */
-	if (!blk_mq_req_expired(rq, next))
-		return true;
-
-	/*
-	 * We have reason to believe the request may be expired. Take a
-	 * reference on the request to lock this request lifetime into its
-	 * currently allocated context to prevent it from being reallocated in
-	 * the event the completion by-passes this timeout handler.
-	 *
-	 * If the reference was already released, then the driver beat the
-	 * timeout handler to posting a natural completion.
-	 */
-	if (!refcount_inc_not_zero(&rq->ref))
-		return true;
-
-	/*
-	 * The request is now locked and cannot be reallocated underneath the
-	 * timeout handler's processing. Re-verify this exact request is truly
-	 * expired; if it is not expired, then the request was completed and
-	 * reallocated as a new request.
+	 * blk_mq_queue_tag_busy_iter() has locked the request, so it cannot
+	 * be reallocated underneath the timeout handler's processing, then
+	 * the expire check is reliable. If the request is not expired, then
+	 * it was completed and reallocated as a new request after returning
+	 * from blk_mq_check_expired().
 	 */
 	if (blk_mq_req_expired(rq, next))
 		blk_mq_rq_timed_out(rq, reserved);
-
-	blk_mq_put_rq_ref(rq);
 	return true;
 }
 
@@ -2155,6 +2135,18 @@ static void blk_add_rq_to_plug(struct blk_plug *plug, struct request *rq)
 	}
 }
 
+/*
+ * Allow 4x BLK_MAX_REQUEST_COUNT requests on plug queue for multiple
+ * queues. This is important for md arrays to benefit from merging
+ * requests.
+ */
+static inline unsigned short blk_plug_max_rq_count(struct blk_plug *plug)
+{
+	if (plug->multiple_queues)
+		return BLK_MAX_REQUEST_COUNT * 4;
+	return BLK_MAX_REQUEST_COUNT;
+}
+
 /**
  * blk_mq_submit_bio - Create and send a request to block device.
  * @bio: Bio pointer.
@@ -2251,7 +2243,7 @@ blk_qc_t blk_mq_submit_bio(struct bio *bio)
 		else
 			last = list_entry_rq(plug->mq_list.prev);
 
-		if (request_count >= BLK_MAX_REQUEST_COUNT || (last &&
+		if (request_count >= blk_plug_max_rq_count(plug) || (last &&
 		    blk_rq_bytes(last) >= BLK_PLUG_FLUSH_SIZE)) {
 			blk_flush_plug_list(plug, false);
 			trace_block_plug(q);
@@ -3135,7 +3127,8 @@ struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set)
 }
 EXPORT_SYMBOL(blk_mq_init_queue);
 
-struct gendisk *__blk_mq_alloc_disk(struct blk_mq_tag_set *set, void *queuedata)
+struct gendisk *__blk_mq_alloc_disk(struct blk_mq_tag_set *set, void *queuedata,
+		struct lock_class_key *lkclass)
 {
 	struct request_queue *q;
 	struct gendisk *disk;
@@ -3144,12 +3137,11 @@ struct gendisk *__blk_mq_alloc_disk(struct blk_mq_tag_set *set, void *queuedata)
 	if (IS_ERR(q))
 		return ERR_CAST(q);
 
-	disk = __alloc_disk_node(0, set->numa_node);
+	disk = __alloc_disk_node(q, set->numa_node, lkclass);
 	if (!disk) {
 		blk_cleanup_queue(q);
 		return ERR_PTR(-ENOMEM);
 	}
-	disk->queue = q;
 	return disk;
 }
 EXPORT_SYMBOL(__blk_mq_alloc_disk);
@@ -3300,8 +3292,6 @@ int blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
 	    set->map[HCTX_TYPE_POLL].nr_queues)
 		blk_queue_flag_set(QUEUE_FLAG_POLL, q);
 
-	q->sg_reserved_size = INT_MAX;
-
 	INIT_DELAYED_WORK(&q->requeue_work, blk_mq_requeue_work);
 	INIT_LIST_HEAD(&q->requeue_list);
 	spin_lock_init(&q->requeue_lock);